Medications for Restless Leg Syndrome
For adults with RLS, start with gabapentin (1200-1800 mg), gabapentin enacarbil (600 mg), or pregabalin (150-450 mg) as first-line pharmacologic therapy, combined with iron supplementation if ferritin ≤100 ng/mL or transferrin saturation <20%. 1
First-Line Treatment Algorithm
Step 1: Iron Repletion (Check First)
- Oral iron: Ferrous sulfate 325-650 mg daily or every other day if ferritin ≤100 ng/mL or transferrin saturation <20% 1
- IV iron (preferred for faster response):
Step 2: Gabapentinoids (First-Line Pharmacotherapy)
The 2025 AASM guidelines provide strong recommendations (moderate certainty evidence) for all three gabapentinoids 1:
- Gabapentin enacarbil: 600 mg once daily (extended-release formulation)
- Gabapentin: 1200-1800 mg divided doses
- Pregabalin: 150-450 mg daily
These achieve ~70% response rates ("much or very much improved") versus ~40% with placebo, without risk of augmentation 2.
Step 3: Second-Line Options
Opioids (conditional recommendation, moderate certainty): Extended-release oxycodone or other opioids for patients who fail gabapentinoids or have severe refractory symptoms 1. Low-dose methadone (5-10 mg daily) is particularly effective for augmented or treatment-resistant RLS 2.
Dipyridamole (conditional recommendation, low certainty): Alternative non-dopaminergic option 1
What NOT to Use as Standard Treatment
Dopamine Agonists: Now Downgraded
The 2025 guidelines represent a major shift from previous practice. The AASM now suggests against standard use of all dopamine agonists due to augmentation risk (7-10% annually) 1, 2:
- Pramipexole (conditional recommendation against)
- Ropinirole (conditional recommendation against)
- Rotigotine patch (conditional recommendation against)
- Levodopa (conditional recommendation against)
Critical caveat: These may still be used short-term in patients who prioritize immediate symptom relief over long-term augmentation risk, but this is no longer standard practice 1.
Strong Recommendation Against
- Cabergoline: Strong recommendation against due to serious adverse events including cardiac valvulopathy 1
Conditional Recommendations Against
Special Populations
End-Stage Renal Disease (ESRD)
- Gabapentin (conditional recommendation) 1
- IV iron sucrose if ferritin <200 ng/mL and transferrin saturation <20% (conditional recommendation) 1
- Vitamin C (conditional recommendation) 1
Children
Ferrous sulfate with appropriate iron parameters (conditional recommendation, very low certainty) 1
Critical Clinical Pitfalls
Augmentation recognition: Symptoms occurring earlier in the day, increased severity, or spread to arms indicate augmentation from dopaminergic therapy. This requires switching to gabapentinoids or opioids, NOT increasing the dopamine agonist dose 3.
Medication withdrawal: When discontinuing dopamine agonists, add the alternative agent (gabapentinoid or opioid) FIRST at therapeutic doses before attempting very slow down-titration of the dopamine agonist to avoid severe rebound RLS 3.
Exacerbating medications to discontinue: Serotonergic antidepressants, dopamine antagonists (antiemetics, antipsychotics), and centrally-acting H1 antihistamines (diphenhydramine) 2.
Iron parameters: Don't wait for frank iron deficiency—treat when ferritin ≤100 ng/mL, which is higher than typical anemia thresholds 2.
Practical Implementation
Start with checking iron studies. If low-normal, give IV iron (ferric carboxymaltose 1000 mg provides fastest response). Simultaneously initiate gabapentin enacarbil 600 mg or pregabalin 150-300 mg at bedtime. Titrate gabapentinoids over 1-2 weeks to effective dose. Reserve opioids for gabapentinoid failures or severe refractory cases. Avoid dopamine agonists for new patients given augmentation concerns, despite their historical use as first-line agents 1, 2, 4.